The present invention relates to a coin return control system for vending machines which returns coins from change retaining tubes instead of from deposited coins.
2. Description of the Prior Art
FIGS. 20 and 21 illustrate two types of conventional coin return control systems In the control systems, a coin deposited into a coin inlet 1 is guided along a coin guide path 2, and tested by a coin testing means 3 to determine its authenticity and type during its passage through the coin guide path. A coin determined to be an unacceptable coin (for example, a metal slug or foreign coin) is distributed to a first coin path 5 by a distributing gate means 4 and returned through a slug chute 10 to a return opening 11.
When a deposited coin is an acceptable coin, and when it is determined to be a five hundred monetary unit coin, it is distributed to a second coin path 6; when it is determined to be a ten unit coin, it is distributed to a third coin path 7; when it is determined to be a fifty unit coin, it is distributed to a fourth coin path 8; and when it is determined to be a one hundred unit coin, it is distributed to a fifth coin path 9, respectively. The deposited coins thus distributed are guided through respective coin paths 6, 7, 8 and 9 and retained in a change retaining tube 12 for five hundred unit coins, a change retaining tube 13 for ten unit coins, a change retaining tube 14 for fifty unit coins and a change retaining tube 15 for one hundred unit coins, respectively.
In the system shown in FIG. 20, after coin testing means 3 determines the type of deposited acceptable coins, the determining signal DS.sub.500 which represents the determination of five hundred unit coin is input to a deposited coin number counter CT.sub.500 for five hundred unit coins; the determining signal DS.sub.10 represents the determination of ten unit coin is input to a deposited coin number counter CT.sub.10 for ten unit coins; the determining signal DS.sub.50 which represents the determination of fifty unit coin is input to a deposited coin number counter CT.sub.50 and the determining signal DS.sub.100 which represents the determination of one hundred unit coin is input to a deposited coin number counter CT.sub.100, respectively. By these inputs, the number of deposit coins in accordance with the type of the deposited coins is counted by each of deposited coin number counters CT.sub.500, CT.sub.10, CT.sub.50 and CT.sub.100.
In the system shown in FIG. 21, the determining signals DS.sub.500, DS.sub.10, DS.sub.50 and DS.sub.100 are also input to a stored coin number counter MS.sub.500 for five hundred unit coins, a stored coin number counter MS.sub.10 for ten unit coins, a stored coin number counter MS.sub.50 for fifty unit coins and a stored coin number counter MS.sub.100 for one hundred unit coins, respectively. The counted numbers are added to predetermined initial values represent values) in stored coin number counters MS.sub.500, MS.sub.10, MS.sub.50 and MS.sub.100, respectively. Stored coin number counters MS.sub.500, MS.sub.10, MS.sub.50 and MS.sub.100 are preset to respective predetermined initial values by input of change running-out detecting signals E.sub.500, E.sub.10, E.sub.50 and E.sub.100 sent from change running-out detecting means 12a, 13a, 14a and 15a provided on respective change retaining tubes 12, 13, 14 and 15. For example, change running-out detecting means 12a for five hundred unit coins detects the change running-out state when the number of five hundred unit coins retained in change retaining tube 12 reaches two, and stored coin number counter MS.sub.500 is set to the preset value "2". Change running-out detecting means 13a for ten unit coins detects the change running-out state when the number of ten unit coins retained in change retaining tube 13 reaches twelve, and stored coin number counter MS.sub.10 is set to the preset value "12". Change running-out detecting means 14a and 15a for fifty unit coins and one hundred unit coins detect the respective change running-out states when the number of either the fifty unit coins or the one hundred unit coins retained in change retaining tubes 14 and 15 reach ten, and respective stored coin number counters MS.sub.50 and MS.sub.100 are set to the preset value "10".
In these systems, when a return signal RS for deposited coins generated by a return signal generating means 100 (for example, a coil return lever) is input to a coin return control unit 17, the coin return control unit outputs paying-out signals P.sub.500, P.sub.10, P.sub.50 and P.sub.100 to a coin paying-out mechanism 16 according to counting signals C.sub.500, C.sub.10, C.sub.50 and C.sub.100 which represent counted numbers of respective deposited coin number counters CT.sub.500, CT.sub.10, CT.sub.50 and CT.sub.100 and detecting signals E.sub.500, E.sub.10, E.sub.50 and E.sub.100 of respective change running-out detecting means 12a, 13a, 14a and 15a (FIG. 20) (and stored number counting signals M.sub.500, M.sub.10, M.sub.50 and M.sub.100 which represent counted numbers of respective stored coin number counters MS.sub.500, MS.sub.10, MS.sub.50 and MS.sub.100 (FIG. 21)), for example so as to return the same type and number as the type and number of the deposited coins. Coin paying-out mechanism 16 returns coins, which are the same type and number as the type and number of the deposited coins, from respective change retaining tubes 12, 13, 14 and 15.
In the system shown in FIG. 21, the paying-out signals P.sub.500, P.sub.10, P.sub.50 and P.sub.100 are also input to corresponding stored coin number counters MS.sub.500, MS.sub.10, MS.sub.50 and MS.sub.100, respectively. Respective stored coin number counters MS.sub.500, MS.sub.10, MS.sub.50 and MS.sub.100 subtract the corresponding paying-out number from the stored number when paying-out signals P.sub.500, P.sub.10, P.sub.50 and P.sub.100 are input, and then, count the present number of the coins retained in respective change retaining tubes 12, 13, 14 and 15, and hold the present counted numbers.
On the other hand, a conventional coin return control system wherein coins are returned by a minimum number of coins is known. For example, when twelve ten unit coins are deposited, the system returns a one hundred unit coin and two ten unit coins.
However, in the systems shown in FIGS. 20 and 21, when a smaller denomination coin which is frequently utilized for change is in its change running-out state, for example, when change running-out detecting means 13a detects the change running-out state of ten unit coins in change retaining tube 13, the change running-out state is canceled only when the smaller denomination coins are deposited, but the smaller denomination coin is again in its change running-out state after the coins are returned. In such a condition, since the change running-out state is not really canceled until a manager for the vending machine supplements the coins for change, the probability that the chance of sale is missed is very high.
In the systems that return a minimum number of coins, there is a drawback in that the vending machine can be used as coin exchange machine.